Advances in aircraft surveillance technology, such as Automatic Dependent Surveillance-Broadcast (ADS-B), support a number of airborne and ground applications; e.g. CDTI (Cockpit Display of Traffic Information) and ACAS (Airborne Collision Avoidance). Among other things, ADS-B provides traffic position and velocity data that can be processed to present a velocity vector associated with a target or neighboring aircraft; i.e. display a line that extends from the displayed traffic symbology and represents the horizontal position of the neighboring aircraft in fifteen seconds. Such traffic data may be presented to one or more onboard displays including, but not limited to, a primary flight display, a multifunction display, and/or navigation display in a top-down, moving map format.
CDTI is just one tool that pilots utilize to update and maintain their situational awareness; however, they are primarily expected to maintain an active out-the-window scanning activity. Thus, pilots will not attend the CDTI for extended periods of time, but will sample the information only periodically. Therefore, the informational display format should be such as to present the information in a manner that promotes at-a-glance situational awareness.
Typically, the above referenced velocity vector represents the momentary velocity corresponding to the most recent sample from the ADS-B system. However, the velocity vector does not indicate whether the traffic target is accelerating, decelerating, or maintaining a substantially constant velocity. Therefore, when a pilot only briefly reviews the CDTI, it is difficult for the pilot to discern if the target is rapidly accelerating (as would be the case when, for example, an aircraft is taking off) or rapidly decelerating (as would be the case when an aircraft has just landed). Thus, in order to accurately predict the relative position of a given traffic target, a pilot would be required to track the target on the CDTI to determine the rate-of-change of the target's velocity (i.e. its acceleration or deceleration). The amount of pilot attention this would require and the time consumed thereby are excessive given the pilot's priority for out-the-window scanning in the terminal area.
Accordingly, it is desirable to provide a system and method for displaying that enables a pilot to rapidly discern not only the horizontal position of a neighboring aircraft and its projected position in fifteen seconds, but also provide an indication of the stability of the neighboring aircraft's velocity vector.
It is also desirable to provide a system and method for displaying a graphical indicator that enables a pilot to efficiently discern whether the velocity vector associated with a neighboring aircraft is stable, increasing, or decreasing.